Breather valve



9 1936- J. D. CRECCA ET AL.

BREATHER VALVE Filed Oct. 18, 1934 INVENTORS n JOHN DCREccA Aw STEPHEN MPHlLuPs Patented Jan. 28, 1936 2,028,756 BREATHER VALVE John D. Crecca, United States Navy, and Stephen M. Phillips, Westbury, N. Y.

Application October 18, 1934, Serial No. 748,864 2 Claims. (01. 277 61) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) means H being any suitable securing means for making a watertight connection between the body such as a tank,

in or the like, with a liquid and roof ill, in this case consisting of a ring I3 seof air to the foregoing concured about the valve body If! by welding or braz- 5 to the roof or deck I2 by welding or brazing l5. The upper end of the valve body abutment for holding a stem 22. A compression spring 25 has been set.

companying drawing,

The figure is a section view of the valve schematically shown in operative position.

There is shown at ill a valve body, preferably made of brass, which is secured at H in the deck rests on the spring seat 44, this spring seat 44 or roof l2 of a ship or tank car, the securing valve 39, a locknut being provided to hold the sleeve 46 in the adjusted position.

The sleeve 46 is hollow as at 51 and the end of the valve stern 4B is guided by passing into this hollow 5| of the sleeve 46. The lower end of the valve body 10 is threaded as at 52 so that it may be secured to a suitable breather pipe 53 suitably secured through the tank or compartment wall or top 54.

In operation, the liquid level 55 within the tank or compartment varies as the oil or other liquid within the tank is being used up or is being re placed therein. It also varies with'variations in temperature, expanding as the temperature increases and contracting as the temperature decreases. Evaporation taking place from the level thereof within the tank likewise varies with the temperature, increasing and causing a pressure as the temperature rises and decreasing of condensing causing a vacuum as the pressure falls.

If no breather pipe were provided, the normal variation in the liquid level 55- would cause the compartment or tank walls to tend to explode as the pressure increases or to tend to collapse as the pressure decreases, forming a vacuum therein. When explosive materials, such as gasoline or oil, are carried within the tank, it is undesirable to allow the fumes to escape promiscuously as the pressure is being relieved and it is likewise undesirable to allow foreign matter such as sea water, spray, or rain water to enter therein to contaminate the same.

With the valve of this invention connected to whenever the pressure within the tank predetermined pressure, for which predetermined pressure the spring 25 of outlet valve 21 has been suitably adjusted, the valve 21 will open allowing the fumes to escape therethrough and through the fire-resistant gauze l9 and apertured cover [8. These fumes being dangerous, it is obviously desirable that they be expelled outside the deck of the ship or the roof of the tank car and it is for this reason that the outlet valve 21 is placed above the deck or roof as shown. By having the surface of the outlet valve 21 convex, as shown, any rain water, sea water, or spray that may have collected thereon may drain out through the apertures in the cover l8. As soon as the pressure within the tank drops to that equal to the spring 25, the valve 21 will close and prevent any excessive loss of fumes.

When the temperature drops or. the oil level is lowered through using up of the liquid, a vacuum will be created within the tan As soon as this vacuum exceeds the strength of the spring 43 in its set pesition, it will cause the inlet valve 39 to open, allowing air to enter the tank through the' apertured cover 35 and fire-resistant gauze as. This inlet valve 39 is located below the deck er roof surface and hence is not exposed to any rain, sea water, or spray, and hence can not draw any moisture into the, tank, thereby preventing contamination of the contents of the tank.

It will be especially noted that this form of breather val've permits locating the inlet or suction valve 39 in a protected position to insure-that absolutely no spray or water may enter the tank the breather valve exceeds through the breather pipe. Also, that any pressure inside the breather pipe sufficient to cause the outlet valve 21 to open is bound to be sufficiently in excess of the external pressure at that time to prevent any possibility of water entering at this point..

It is to be noted that fuel or other liquid tanks are generally built to withstand a pressure of at least four pounds per square inch. Thus the spring 25 regulating the outlet valve 21 can be set to cause the outlet valve'to function at any pressure up to four pounds per square inch without strainingthe tank. For sea-going vessels, this would permit installing these valves on the weather deck and the valve would function with seas washing over the deck. Such condition would occur when transferring oil from one tank to another at sea. A sea washing over the weather deck might cover the valve for several feet but the outlet valve 3' would still operate and permit air to escape as the tank is beingfilled by transfer of fluid from another tank. For ordinary pressure the spring would be set for l to 1 pounds per square inch. With thevalve spring set for this pressure the foregoing operation when submerged is still effective as the hydrostatic pressure on the top of the valve will augment the compression on the spring. Under such conditions the valve will not open until the pressure inside the tank, the breather pipe, and

the outside hydrostaticpressure plus the compression in the spring and when this occurs water is prevented from entering by the excess of the internal pressure over the external pressure, thereby absolutely excluding water from entering the ships tank or compartment even though it is discharging under water.

The invention described herein may be manufaetured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

We claim: 4

1. A breather valve comprising a valve body adapted to be secured through a wall or deck, an outlet valve in said valve body located without the deck or wall, and aninlet valve in said valve body located within said deck or wall, compression spring means pre-determining the pressure at which said valves will operate, and means accessible outside -of said valve body for adjusting said pressure determining means, said pressure determining adjusting means comprising in the caseof said outlet valve a valve stemthreadedly secured at one end through said outlet valve, a tool cooperating means on said valve stem for adjusting said valve stem relative to said valve, a valve guide secured withinsaid valve body, said valve stem slidably passing through said valve guide, a head formed on the other end of said valve stem, a spring seat on said valve stem rest= ing against said head, said compression spring means being secured between said spring seat and said valve guide. l

2. A breather valve comprising a valve body adapted to be secured through a wall or deck, an outlet valve in said valve body located without the deck or wall, and an inlet valve in said valve body located within said deck or wall, compression spring means pre-determining the pressure at which said valves will operate, means accessible outside of said valve body for adjusting said pressure determiningmeans, said pressure determining adjusting means comprising in exteriorly of said valve body, a spring seat sethe case of said inlet valve an inlet valve stem cured on said sleeve Within said valve body and said valve stem being slidable within said sleeve, JOHN D. CRECCA. tool cooperating means formed on said sleeve STEPHEN M. PHILLIPS. 

